While the word “nest” immediately evokes images of birds, mammals—including several rodent species—also construct nests. Among them, the squirrel’s drey often masquerades as a bird’s nest, as both are situated high in trees and share a similar round form crafted from twigs and leaves. A casual glance may trick you, but a closer look uncovers distinctive traits.
Scientific terminology calls a squirrel’s nest a drey. They typically measure one to two feet in diameter, noticeably larger than most avian nests. Raptor nests—such as those of hawks and eagles—feature flat, platform‑like tops, whereas a drey is distinctly round and possesses a concealed entrance along the trunk. Birds usually rely on sticks alone; squirrels incorporate abundant foliage, giving the drey a dense, leafy exterior. A nest dominated by leaves and a sizable round shape usually signals a squirrel drey.
Like birds, squirrels build nests to protect their offspring during the early stages of life. With several litters per year, they require a secure shelter to shield vulnerable juveniles from predators. Unlike many bird species that abandon their nests once the young fledge, squirrels may use a single drey year‑round as a safe refuge for sleeping and rearing offspring.
During winter, squirrels may relocate to more insulated sites—tree hollows or even human attics—though many still use their dreys, huddling together for warmth. When occupying a hollow, they line it with leaves, mirroring the construction of a drey.
Although a drey may appear ruff, its construction is deliberate and precise. A framework of interwoven twigs is first erected, then packed with foliage. In cities, squirrels sometimes incorporate discarded human waste—such as plastic bags—into the structure. The resulting drey is tightly packed, rendering it waterproof and sheltering occupants from rain and snow.
Different squirrel species craft distinctive dreys, and the materials used can reveal the builder. In the U.S., the eastern gray squirrel and the red squirrel are the most prevalent. Gray squirrels typically build their dreys in deciduous trees—broad‑leaf species that shed leaves annually—such as oak, a tree prized for its acorns.
Drey construction often reflects dietary habits. Eastern gray squirrels favor acorn‑bearing oaks, whereas red squirrels, whose diet centers on pinecones, construct dreys in conifers, utilizing bark strips. Flying squirrels also build dreys, though their nocturnal habits make them hard to spot. These nests are compact, crafted in conifers from shredded bark, moss, and lichen. During cold periods, up to ten flying squirrels may cluster inside, forming a cozy group.
